XM-18 and XM-24 Knives - Generations, History and General Information

RDA · Jan 5, 2013

There always seems to be a bit of confusion on the different generations of XM Folding Knives so the following is a basic summary of the different generations currently:

XM-18 (3.0") - Gen 1, Gen 2 and Gen 3

Gen1 - The G10 handle is reinforced with a full titanium liner. Hand ground and "R. HINDERER" engraving on the blade. Lockbar Stabilizer disk has the "HINDERER" engraving.
Gen2 - Blades are either hand ground or CNC'd but NO more "R. HINDERER" engraving. The "HINDERER" logo is now on the Ti handle lockside.
Gen3 - Same as Gen2 except the stop pin is mounted differently (similar to Gen4 XM-18 3.5").

XM-18 (3.5") - Gen 1, Gen 2, Gen 3 and Gen 4

Gen1 - Handle is G10 on one side and the lockside had a titanium half liner milled into the G10 scale. Hand ground and "R. HINDERER" engraving on the blade. Old school barrel thumbstuds.
Gen2 - The G10 handle is reinforced with a Ti liner. Hand ground and "R. HINDERER" engraving on the blade. Lockbar Stabilizer disk has the "HINDERER" engraving.
Gen3 - Blades are either hand ground or CNC'd but NO more "R. HINDERER" engraving. The "HINDERER" logo is now on the Ti handle lockside.
Gen4 - Same as Gen3 except the stop pin is mounted differently.

XM-24 (4.0") - Gen 1 and Gen 2

Gen 1 - Handle and lockside are titanium. Hand ground blades (variety of finishes). There were only ten of the Gen 1 XM-24 in all Ti with the Maltese Cross.
Gen 2 - Blades can be either hand ground or production. The "HINDERER" logo is on the Ti handle lockside like the Gen 3 3.5" XM-18 (and they are otherwise consistent with the Gen 3 3.5" XM-18).

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XM-18 (3.5") - Generation 1 - This is the one that started it all for the XM Series of tactical knives back in approximately February 2006. Rick wanted to take the Gen II Flame design and make a new concept in framelock folders, reducing the weight by using G-10 handle material on the non-lockside to make a working knife that was easy to carry. The G-10 was textured to provide more grip and enlarged the thumbstud to allow for easier opening when wearing gloves. In an effort to improve the rigidity of the G-10 non-lockside, Rick embedded a halfliner of 0.050" thick titanium on the backside of the G-10 that also provided a solid lockup point for the 1/4" barrel thumbstud (which also serves as the bladestop when open). The stop pin when the blade is closed is secured to the frame side and doesn't go all the way to the liner side. The halfliner of titanium extends the full length of the knife providing a solid foundation for the over-sized standoffs. The standoffs are 3/8" in diameter with a 3/16" shaft going through them to the opposite side and then screwed in place by three 6/32 stainless screws. The pivot was designed specifically for the introduction of this knife with a 1/4" shaft with a 3/8" head made from hardened 17-4PH Stainless Steel with a 8/32 screw threaded the entire length of the pivot. The pivot was purposefully designed with a straight slot to allow easy field adjustment. This XM sports Rick's signature "Hinderer" lockbar stabilizer and a titanium clip that allows for tip up or tip down carry.

The name of the knife (XM-18) was derived from Rick who considered the knife an "eXperimental Model", hence XM and the 18 was the name of Rick's unit number at the fire department. The knife debuted in Vegas at a table price of $385 (which is unchanged to this day).

All of the knives were custom hand ground by Rick including the signature spanto grind along with some rarer versions (e.g. hellfire). The blades were offered in both flipper and non-flipper versions. The original G-10 colors were black, orange, blue, green, tan, blue/black, and green/black (and there were some other handle materials like micarta). The titanium handle side was offered in stonewashed, bead blasted (a matte smooth finish) or sand blasted (a darker matte and rougher finish).

General Specifications:
Blade Length: 3.50"
Handle Length: 4.75"
Overall Length: 8.25"
Blade Thickness: 0.165"
Lockside Thickness: 0.165"
Liner Thickness: 0.050"
Overall Handle Thickness: 0.540"
Weight: 5.6oz
Blade Steel: CPM S30V & Duratech 20CV

XM-18 (3.5") - Generation 2 - Introduced in approximately December 2006, the second generation of the 3.5" XM-18 had some of the same design changes as the first generation 3.0" XM-18. This XM now included a full titanium liner with "R. HINDERER" engraved on the blade and the Lockbar Stabilizer disk had the "HINDERER" engraving as well. Carbon fiber scales were introduced as well.

General Specifications: (same as above, exceptions noted below)
Blade Steel: Duratech 20CV

XM-18 (3.5") - Generation 3 - Introduced in approximately May 2008 and debuted at Blade 2008, these were the first knives that had the production spanto grind available (custom hand ground blades were also still available) and towards the end of the third generation, the production slicer grind was introduced. The blade no longer included the "R. HINDERER" engraving, instead, the "HINDERER" logo is now on the Ti handle lockside.

General Specifications: (same as above, exceptions noted below)
Blade Steel: Duratech 20CV & Carpenter CTS-XHP & Crucible CPM-S35VN & Carpenter CTS-40CP

XM-18 (3.5") - Generation 4 - Introduced in approximately October 2011, this generation of XM-18 moved the stop pin from the old location to other side of the knife contacting the spine side (rather than the choil side) and was the full width extending from the lockside to the liner side. This change would allow for the elimination of the choil and different potential grinds.

General Specifications: (same as above, exceptions noted below)
Blade Steel: Duratech 20CV & Crucible CPM-S35VN

XM-18 (3.0") - Generation 1 - Introduced in approximately October 2006, the first generation of the 3" XM-18 had some design changes compared to the first generation 3.5" XM-18. This XM now included a full titanium liner with "R. HINDERER" engraved on the blade and the Lockbar Stabilizer disk had the "HINDERER" engraving as well.

All of the knives were custom hand ground by Rick including the signature spanto grind along with some rarer versions (e.g. hellfire). The blades were offered in both flipper and non-flipper versions. The G-10 colors were extensive and the titanium handle side was offered in stonewashed, bead blasted (a matte smooth finish) or sand blasted (a darker matte and rougher finish).

General Specifications:
Blade Length: 3.0"
Handle Length: 4.125"
Overall Length: 7.00"
Blade Thickness: 0.140"
Lockside Thickness: 0.125"
Liner Thickness: 0.050"
Overall Handle Thickness: .425"
Weight: 3.6oz
Blade Steel: Duratech 20CV

XM-18 (3.0") - Generation 2 - Introduced in approximately May 2009 (Blade Show), this generation included the same changes as the third generation of 3.5" XM-18 including the production spanto grind (first run) and the production slicer grind (second run) and custom hand ground blades as available. The blade no longer included the "R. HINDERER" engraving, instead, the "HINDERER" logo is now on the Ti handle lockside.

XM-18 (3.0") - Generation 3 - Introduced in approximately May 2014 (Blade Show), this generation included the same changes as the fourth generation of 3.5" XM-18 where the stop pin was moved from the old location to other side of the knife contacting the spine side (rather than the choil side) and was the full width extending from the lockside to the liner side. This change would allow for the elimination of the choil and different potential grinds. This generation saw the introduction of the production wharnie grind (first run).

XM-24 (4.0") - Generation 1 - These debuted approximately October 2008. The handle and lockside are titanium with hand ground blades (variety of finishes). There were only ten of the first generation XM-24 in all Ti with the Maltese Cross. The "HINDERER" logo is was on the Ti handle lockside. Due to the added heft of the blade, the stop pin was the full width extending from the lockside to the liner side.

General Specifications:
Blade Length: 4.00"
Handle Length: 5.625"
Overall Length: 9.125"
Blade Thickness: 0.185"
Lockside Thickness: 0.185"
Liner Thickness: 0.050"
Overall Handle Thickness: 0.590"
Weight: 7.8oz
Blade Steel: D2 Tool Steel

XM-24 (4.0") - Generation 2 - Introduced in approximately June 2010 (Blade Show), this generation included the same changes as the third generation of 3.5" XM-18 including the production spanto grind and the production slicer grind and custom hand ground blades as available. The "HINDERER" logo is on the Ti handle lockside.

General Specifications: (same as above, exceptions noted below)
Blade Steel: Carpenter CTS-XHP & Crucible CPM-S35VN

Credits:

Photos courtesy of Rick Hinderer Knives (http://www.rickhindererknives.com), Rob Orlando and Josh Bryant
Most of the information was gleaned from Rick Hinderer, Rob Orlando and Mike Kammer via conversations and public posts/comments.

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If anyone has anything they would like to see added, send me a PM and I'll do my best to incorporate it. This will be a work-in-progress so please give me some time to work on it. Any errors or omissions, don't hesitate to contact me.

RDA · Jan 5, 2013

Hardware:

The standard screws, receivers, standoffs, lockbar stabilizer (LBS) and pivot components are 17-4PH stainless steel. Everything is currently made in house with the exception of the clip screws.

Clip Screws – The clip screws are 1/8” 2-56 and they appear with a variety of heads. Torx was the first style used (T6 drive) until switching over to Allen (hex) which is 0.050” drive. Around October, 2009, the screws changed to Phillips drive and #1 works very well.

Thumbstuds – The first thumbstuds were cylindrical with a cross hatched design around the perimeter and a divot in the middle (primarily seen on Gen 1 3.5” XM-18). The second version of the thumbstud to appear was smooth stepped version. The third and most recent version of the thumbstud was an evolution of the prior version but was now sporting a rounded edge (commonly referred to as “domed&#8221

and was introduced approximately the same time as the Gen 4 3.5” XM-18 (November 2011).

Standoff Screws - Early versions had the rounded head and were Torx drive (T8). Ultimately, Rick began manufacturing these screws in house and they became the flat head version and were hex drive. There was an early issue early related to the flat head screws and the female portion of the hex being too deep and not having enough material left in the screw head allowing them to twist off too easily but that was quickly corrected and Hinderer Knives has and will replace those problematic screws under warranty. The following are the two sizes of hex head screws used:

3.5" and 4.0" use 5/64" female hex head standoff screws.
3.0" uses a 1/16" female hex head standoff screws.

LockBar Stabilizer (LBS) – All three sizes of knives take the same lockbar stabilizer and screw, whether the stock stainless version, the titanium version or the Steel Flame version.

Optional Hardware and Components:

During 2013, Hinderer Knives introduced hardware in various metals as follows:

Pivot Screw – Titanium pivot screws, in natural (plain) as well as blue and bronze anodization. These are occasionally available directly from their website.
Thumbstuds – Titanium thumb studs, in natural as well as blue and bronze anodization. These have been seen on select custom knives.
Standoff Handle Screws - Titanium standoff handle screws, in natural as well as blue and bronze anodization. These are occasionally available directly from their website.
Standoffs- Titanium standoffs, in natural (plain) as well as blue and bronze anodization. Also, these have been made in copper and brass as well. These are occasionally available directly from their website.
LockBar Stabilizer (LBS) – The LBS has been seen in titanium (in natural as well as blue and bronze anodization) as well as brass. These have been seen on select custom knives.

Armorer’s Tool:

In February, 2008, Rick introduced his complete disassembly and spanner tool for the XM which makes it very easy to hold both the wrench and the knife at the same time with one hand. On the second part of the tool, which unscrews from the main body, is the screw driver blade that perfectly matches the slot on the pivot screw of the XM. In addition, on the inside of the male portion is a female drive that accepts 1/4” hex drive bits (5/64” hex drive bit included with the tool). The male end also sports a cross drilled hole so you can use it as a "T" wrench for extra torque. The tools are made from either 17-4 PH stainless or titanium. The tool measures approximately 2 1/2" in length so you can store this anywhere or even add it to your key ring!

Use of Loctite:

Hinderer Knives only recommends Blue Loctite on the pivot screw (sparingly). Don’t use loctite on any of the other screws (i.e., the standoff screws, the pocket clip screws, the LBS screw). If you don’t want to use the Blue Loctite, I recommend Vibra-Tite VC-3 on the pivot screw.

Titanium Scales:

The first use of titanium scales came on a select number of 3” XM-18s and also the Gen 1 XM-24s (noted above) which were specific to their respective model. As a result of their popularity, replacement titanium scales were introduced for the current XM generations in August 2011 and made available in October 2011 as either smooth titanium or Hinderer’s signature textured version (in a variety of finishes and/or annodization). Frag versions via Monkey Edge followed shortly thereafter. The Titanium Scale replaces the stock G10/Titanium liner. Weight comparison are as follows:

XM-18 (3.0") - equipped with G10/Titanium liner - 3.6 oz.
XM-18 (3.0") - equipped with Hinderer Titanium Scales - ~4.1 oz.
XM-18 (3.5") - equipped with G10/Titanium liner - 5.6 oz.
XM-18 (3.5") - equipped with Hinderer Titanium Scales - ~6.4 oz.
XM-24 (4.0") - equipped with G10/Titanium liner - 7.8 oz.
XM-24 (4.0") - equipped with Hinderer Titanium Scales - ~8.7 oz.
XM-24 (4.0") - equipped with Titanium Frag Scales - ~8.9 oz.

The titanium scales are occasionally available directly from their website.

Laser Marking:

In 2012, Hinderer Knives began laser marking the knives. The custom knives receive the horse head logo and Rick’s signature whereas the productions receive the horse head logo and the “Made in the USA” and blade steel designation on the opposite side.

Grinds:

There are quite a few different grinds available on XMs and the list continues to grow:

Spanto (both production and custom)
Slicer (both production and custom)
Wharncliffe or Wharnie (both production and custom)
Spearpoint
SWAT (serrated spanto)
Hellfire
Recurve
Bowie
Armoured Bowie
Skinner
Agressor Tanto
Dagger
Spearpoint Dagger
Harpoon
Compound

Interesting Tidbits of XM Information (FAQ):

I am curious why there is discoloration in the pivot screw slot and gimping? This is a product of heat treat, the discoloration results and it is retained in those areas that don’t receive any further machining/tumbling/etc.

Why doesn’t the scale thumb cutout match the cutout on the liner? Rick designed the XM that way intentionally, by making the scale side the same profile as the lockside, it reduces the chance that your finger unintentionally disengages the lock.

What are the washers made of? They are Teflon and the smaller outside diameter washer goes on the lockside with the larger one on the scale side.

Is your filler tab stuck? Take a small hex wrench just small enough to fit in the filler tab hole and pry it out. Other alternatives include a toothpick, small screwdriver, drift pin, etc.

What is the story on the lockbar stabilizer (LBS) and what purpose does it serve? Rick overextended a lockbar on one of his personal knives he was using in an emergency as a fireman while dealing with a car accident. This led to Rick designing his LBS to avoid overextending the lockbar and preventing potential loss of lock-up.

What is the difference between stonewashing (tumbling), working finish, and blasting? There are a variety of surface finishes used on XMs as follows:

Stonewashing is one of the more common treatments, it consists of tumbling the metal parts with ceramic media to impart random scratches
The working finish results when they take a ground or tumbled part, it is then sand blasted and then tumbled with ceramic media for a short period resulting in a hybrid blasted/tumbled finish.
Blasting can either be sand or bead, sand blast is coarser and generally appears darker while the bead blast is smoother and more matte.
Satin / Hand Rubbed results when the blade is hand ground by Rick and the flats (either blade and/or Ti lockside) are hand rubbed.

Why is my detent too light/too tight/just right?Quite simply, this is one of those cases where you just won't make everyone happy (Goldilocks syndrome). Rick has worked hard to make the detent just right. If 90% are happy with the detent, while 5% say it is too light and 5% say it is too tight, the detent is in the sweet spot for all intents and purposes. If you aren't happy with it, you might try tweaking the lockbar some (towards the lock if you feel the detent could be tighter or towards the outside if you want it to be lighter) by disassembling the lockside. Don't overadjust or overspring the lockbar and if you aren't comfortable disassembling/reassembling your XM, then it is best you don't mess with the lockbar.

Rob described it better than I could with this:

There are 3 ways to deploy an XM, the thumbstud, the flipper, and inertia opening, so yes you can expect it to open when shaken. It is no mystery, nor does it have anything at all to do with user error. We build them to a certain spec, it is not for everyone.

Credits:

Photos courtesy of Rick Hinderer Knives (http://www.rickhindererknives.com), Rob Orlando and Josh Bryant
Most of the information was gleaned from Rick Hinderer, Rob Orlando and Mike Kammer via conversations and public posts/comments.

Note: Most recent changes in blue

RDA · Feb 22, 2013

Test........

Need2Know · Feb 24, 2013

R--

May want to update with some information about the new blade markings on the current XMs. May prove easier to add updates/edits while information is topical than rely on memory later.

Rice man · Mar 4, 2013

Thanks for that, It is cool seeing the development of the Hinderer knives of time.

denari · Mar 23, 2013

Hi RDA,

First of all, thanks for the writeup.

May I also add that the Gen 4's also have a rounder dome shaped thumbstuds.

Also, do you have more information about customs?
Things like the various grinds / finishes that only appear on the customs and the handle configurations used (smooth CF, G-10 + beadblast Ti, etc.)

Need2Know · Mar 23, 2013

denari said:
Hi RDA,

First of all, thanks for the writeup.

May I also add that the Gen 4's also have a rounder dome shaped thumbstuds.

Also, do you have more information about customs?
Things like the various grinds / finishes that only appear on the customs and the handle configurations used (smooth CF, G-10 + beadblast Ti, etc.)

Thumb stud info you posted is not entirely accurate. Either style can appear at any time. I've got a Gen 4 3.5 and no domed studs...flat-top volcano type.

denari · Mar 23, 2013

Need2Know said:
Thumb stud info you posted is not entirely accurate. Either style can appear at any time. I've got a Gen 4 3.5 and no domed studs...flat-top volcano type.

Could the flat ones appear in the unmarked Gen4's while the rounded ones on the Gen4's with new logos?
I'm rather new to Hinderers really.
Only handled the new logo blades so far.

RDA · Mar 23, 2013

denari said:
Hi RDA,

First of all, thanks for the writeup.

You are welcome.

denari said:
May I also add that the Gen 4's also have a rounder dome shaped thumbstuds.

Actually, the rounder dome shaped thumbstud is not specific to the Gen 4 3.5" XM-18, I have commented on this before:

http://www.bladeforums.com/forums/s...-Spanto-Video-Review!?p=10488996#post10488996
http://www.bladeforums.com/forums/showthread.php/979183-Gen-4-XM-18-3-inch?p=11143239#post11143239

All current XMs use both versions of current thumbstud ("dome" and "volcano").

denari said:
Also, do you have more information about customs?
Things like the various grinds / finishes that only appear on the customs and the handle configurations used (smooth CF, G-10 + beadblast Ti, etc.)

I have a second draft of the original post that I have been working and I have been accumulating info that seems to be commonly asked or I have answered a number of times that I plan to add that most should appreciate and hopefully find useful.

denari said:
Could the flat ones appear in the unmarked Gen4's while the rounded ones on the Gen4's with new logos?
I'm rather new to Hinderers really.
Only handled the new logo blades so far.

No, see my comments above. Both styles of thumbstuds exist in the parts bins at Hinderer Knives, when they assemble knives, whether custom or production, they can pick from either style.

Gress · Mar 31, 2013

I think that one more thing should be mentioned.
In between 3.5xm gen 3 and gen 4 there was a change with regard to the blade tang. AFAIK the new tang design started somewhere in Nov-Dec 2010 and continues from that time on. So perhaps we can distinguish a 3.5 XM gen 3.5

The old tang was a full length and the new one has a cut-out.

Here are the pictures of my two knives showing the difference.
Old:

New:

Mountain Wildman · May 3, 2013

Question: Can someone tell me the sharpening angle on my Gen. 2, XM-24
While doing a push cut the blade struck against metal and put 2 nicks in the tip area of the blade
and I want to use my Wicked Edge to remove them and re-sharpen the blade.
Thanks!!
Joseph

phm14 · May 18, 2013

Thank you. I just recently started hunting XMs, so this is very helpful.

RDA · May 18, 2013

phm14 said:
Thank you. I just recently started hunting XMs, so this is very helpful.

Welcome and that was precisely the purpose, to help get people up to speed some on the XMs.

markandrex · Jan 2, 2014

Great reference to those new to RHK! That would be me, thanks!

RDA · Jan 2, 2014

markandrex said:
Great reference to those new to RHK! That would be me, thanks!

Great and welcome to RHK.

ctalon · Jan 13, 2014

Were the blades of the 3rd gen XM-18 3.5's marked with their blade steel? I have a number of them that are sterile and I was told at purchase that they were CTS-XHP.

RDA · Jan 13, 2014

ctalon said:
Were the blades of the 3rd gen XM-18 3.5's marked with their blade steel? I have a number of them that are sterile and I was told at purchase that they were CTS-XHP.

As noted above, the following were the blade steels that came on the Gen 3 XM-18 3.5":

Blade Steel: Duratech 20CV & Carpenter CTS-XHP & Crucible CPM-S35VN & Carpenter CTS-40CP

If it is sterile, the steel should be Duratech 20CV. The other options are marked on the steel.

Dknight16 · Apr 13, 2014

Are there any generational changes to the 2014 produced 3 inch XM-18s w/ logo and USA marks?

kwazyjuice · Apr 13, 2014

It seems like that is the only change as far as I have seen, the logo and steel laser engravings. The stop pin is still in the same place. But I'm sure RDA can chime in

RDA · Apr 14, 2014

kwazyjuice said:
It seems like that is the only change as far as I have seen, the logo and steel laser engravings. The stop pin is still in the same place. But I'm sure RDA can chime in

The current production 3" knives should still be Gen 2 AFAIK as there were no plans to change the stop pin location (like Gen 4 3.5" models) or do anything else that would constitute a material change in Rick's mind that I am aware of. I'll let you know when I get my 3" wharnie...